CONTENTS OF VOL. XX. VII 



IVIOLiLXJSCA. 



Page 

 Sur quelques Cephalopodes du Musee Royal de Leyde et description de trois 



espèces nouvelles. Par M. L. Joubin 21. 



Conchological corrections and additions. By M. M. Schepman 84. 



Description of a new Unio from Borneo. By M. M. Schepman. (Plate 1, 



figs. 1 and 2) 92. 



VERIMES. 



Aspidosiphon cylindricus, n. sp. By Dr. R. Horst. (With figures) 195. 



On the variahility of characters in Perichaetidae. By Dr. R. Horst. . . . 201. 



On Perichaeta Sieboldi Horst. By Dr. R. Horst 240. 



